Context: disc environments Results: embedded planet core Ambipolar diffusion and core accretion in layered protoplanetary discs Oliver Gressel ⋆ Niels Bohr International Academy (NBIA), Copenhagen Richard P . Nelson (QMUL, London) Neal J. Turner (JPL-Caltech, Pasadena) Colin P . McNally (NBIA, Copenhagen) Udo Ziegler (AIP , Potsdam) 6th - 8th May, 2015 Exoplanets in Lund meeting ⋆ oliver.gressel@nbi.dk O. Gressel 2015-05-06 – Lund, Sweden 1/15
Context: disc environments Results: embedded planet core protoplanetary environments Image Credit: HST Image Credit: NASA O. Gressel 2015-05-06 – Lund, Sweden 2/15
Context: disc environments Results: embedded planet core determining the disc structure ... Semenov & Henning (2012) � irradiation (UV, X-Ray, CR) → heating (vertical hydrostat. eq.) / ionisation ( → MHD) � dust settling/growth/destruction/transport � MRI feedback (turbulence, heating) � dust opacities (UV → IR, optical depths) � chemistry (condensation, freeze-out) � snow/ice-lines, gap/dead-zone edges → vortices, planet traps O. Gressel 2015-05-06 – Lund, Sweden 3/15
Context: disc environments Results: embedded planet core disc ionisation chemistry irradiation (FUV, X-Ray, CR), radioactive decay → ionising events recombination with gas-phase ions/molecules, absorption on sub-micron dust grains non-ideal MHD effects (Ohmic, Hall, AD) all important Bai & Stone (2013), Bai (2013), Simon et al. (2013), Bai (2014a/b), Kunz & Lesur (2013), Lesur, Kunz & Fromang (2014), Gressel, Turner, Nelson & McNally (2015) O. Gressel 2015-05-06 – Lund, Sweden 4/15
Context: disc environments Results: embedded planet core gas giant interiors Image Credit: NASA, Lunar and Planetary Institute O. Gressel 2015-05-06 – Lund, Sweden 5/15
Context: disc environments Results: embedded planet core motivation our goals core accretion picture identify . . . accretion time-scales 1D spherical envelopes role of circumplanetary disc I: quasi-static contraction potential bottle-necks II: runaway growth phase influence of magnetic field O. Gressel 2015-05-06 – Lund, Sweden 6/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) global disc simulations Gressel et al. (2013) O. Gressel 2015-05-06 – Lund, Sweden 7/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) global disc simulations Gressel et al. (2013) O. Gressel 2015-05-06 – Lund, Sweden 7/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) embedded sub-disc isothermal HD non-isoth. HD non-isoth. MHD O. Gressel 2015-05-06 – Lund, Sweden 8/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) embedded sub-disc isothermal HD non-isoth. HD non-isoth. MHD O. Gressel 2015-05-06 – Lund, Sweden 8/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) embedded sub-disc isothermal HD non-isoth. HD non-isoth. MHD O. Gressel 2015-05-06 – Lund, Sweden 8/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) circumplanetary disc variability O. Gressel 2015-05-06 – Lund, Sweden 9/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) circum-jovian jet � predicted theoretically by Quillen & Trilling (1998) and Fendt (2003) O. Gressel 2015-05-06 – Lund, Sweden 10/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) adding ambipolar diffusion external ionisation via X-Rays, CRs, new: FUV layer Ohmic resistivity, new: ambipolar diffusion (no) magnetorotational instability (MRI) → (no) turbulent surface layers magneto-centrifugal (laminar) disc winds effect of reduced gas column in the gap region ionisation state of the CPD effect on jet launching magneto-centrifugal wind from PPD with AD Gressel, Nelson, Turner & McNally (2015) O. Gressel 2015-05-06 – Lund, Sweden 11/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc winds � quasi-MMSN disc model, NVF with midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 12/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc winds � quasi-MMSN disc model, NVF with midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 12/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc winds � quasi-MMSN disc model, NVF with midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 12/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc winds � quasi-MMSN disc model, NVF with midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 12/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc winds � quasi-MMSN disc model, NVF with midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 12/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) reduced dust fraction � quasi-MMSN disc model, midplane β p 0 = 10 5 , d/g mass ratio 10 − 4 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 13/15
Context: disc environments Ohmic dissipation only Results: embedded planet core new microphysics (AD) laminar disc with embedded planet � quasi-MMSN disc model, midplane β p 0 = 10 5 , d/g mass ratio 10 − 3 , XR+CR+FUV O. Gressel 2015-05-06 – Lund, Sweden 14/15
summary of results Core accretion spin-out circumplanetary disc mainly vertical inflow of low-metallicity gas → efficient cooling of contracting envelope (!?) high accretion rate ( ∼ 8 × 10 − 3 M ⊕ yr − 1 ) Saturn → Jupiter in ∼ 30 , 000 yr Launching of a “circumplanetary” jet tornado-like flow drags down azimuthal field swirling → helical field → magneto-centrifugal jet disc outflow important for CPD evolution (!?) Including additional microphysics magneto-centrifugal disc wind with AD evolution of embedded sub-disc – work in progress O. Gressel 2015-05-06 – Lund, Sweden 15/15
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